Project Parameters
Total square footage of your lawn (length × width).
Instant Estimate
Starter Fertilizer Needed
Applied at 4 lbs per 1,000 sq ft to nourish young seedlings.
Compost / Peat Top Dressing (¼ in)
Protects seed from birds and retains critical soil moisture.
Coverage Area
Application Rate
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Guide
How to calculate grass seed for your lawn
Grass seed quantity depends on species seed density. Kentucky bluegrass has millions of microscopic seeds per pound and requires only 2–3 lbs per 1,000 sq ft, whereas tall fescue and ryegrass have larger seeds requiring 6–8 lbs per 1,000 sq ft.
Measure Lawn Area
Divide irregular yards into rectangles or triangles, calculate square footage, and subtract driveways and patios.
Select Your Grass Type
Cool-season grasses (Fescue, Bluegrass) grow best in northern regions; warm-season grasses (Bermuda, Zoysia) excel in the south.
Adjust for New vs Overseeding
Use 100% of the recommended rate on bare dirt; reduce to 50% rate if thickening an already established lawn.
Mathematics
Formulas used
Seed Weight
(Lawn Sq Ft / 1,000) × Species Seed Rate × Project MultiplierPounds of grass seed needed for optimal sprout density.
Starter Fertilizer
(Lawn Sq Ft / 1,000) × 4 lbsStandard high-phosphorus starter fertilizer application rate.
Answers & FAQ
Frequently asked questions
How many pounds of grass seed do I need for 5,000 sq ft?▼
For tall fescue, you need about 40 lbs for a new lawn (or 20 lbs for overseeding). For Kentucky bluegrass, you need 15 lbs for a new lawn.
Can you put down too much grass seed?▼
Yes. Oversaturating soil causes seedling crowding, where baby grass plants compete for limited water and nutrients, resulting in weak roots and fungal disease.
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